<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <div id="app">
        姓: <input type="text " v-model="xing"> </br>
        名: <input type="text " v-model="ming"> </br>
        姓名 <span>{{ xing.slice(0,3) }}-{{ming}}</span>
    </div>
    <script src="../JS/vue.js"></script>
    <script>
        new Vue({
            el:'#app',
            data(){
                return{
                    xing:'张',
                    ming:'三'
                }
            },
        })
    </script>
</body>
</html>